This invention relates to the manufacture of shoes of the type having uppers comprising parts of flexible sheet material that are joined by stitching.
In the manufacture of shoes of the type employed in athletics, for example, it is common practice to form a shoe upper by assembling a plurality of parts of flexible sheet material, such as parts made of fabric or plastic, and joining them by stitching. In mass production, the stitching is performed by an automatic sewing machine, with the parts to be joined sandwiched between a base plate and a hinged cover plate of a pallet. The pallet includes a template with cavities for locating the parts to be joined, and the pallet is provided with appropriate openings to permit stitching therethrough. After assembly in the pallet of the parts to be joined, the pallet is placed on an X-Y traverse mechanism or carriage that automatically moves the pallet horizontally in two directions while stitching is performed by one or more stitching heads. Although apparatus of this type is capable of excellent performance, the pallets are complex, and the quality of the finished upper is dependent upon the skill of the operator, who is required to position the upper parts to be joined on the pallet with a high degree of accuracy.